Vasoactive Intestinal Peptide (VIP) is one of the most highly-utilized regulatory peptides in vertebrates, its expression in the central and peripheral nervous systems impacting on neurological, cardiovascular, pulmonary, gastrointestinal, and reproductive function. In the brain and peripheral nervous system, the peptide appears to have an important role in cell growth, survival, maturation and phenotypic maintenance. The objective of this work is to identify the sequences on the vasoactive intestinal peptide (VIP) gene that activate its expression in appropriate tissues during development and that maintain the gene in a transcriptionally active state in the adult. We will pursue this objective by preparing chimeric VIP/reporter genes that contain normal and mutant forms of VIP regulatory sequences and analyze their expression in transgenic mice, and in transfected cells in culture (primary cells, neuroblastoma cell lines, and immortalized neurons). A protein previously found to bind to VIP gene transcription control sequences will be isolated (and/or cloned), characterized, and its expression mapped at the level of the mRNA, and protein. We will also begin to isolate a different protein that controls another aspect of VIP expression based on the data obtained in the transgenic mouse model. Our ultimate goal is to determine how these proteins control the expression of the VIP gene, and what their role is in the establishment and maintenance of VIP-expressing phenotypes.